#5 Introduction to sound:

Objective: 

By using Labpro to capture the wave pattern of certain sound wave, we can further understand the property of sound.

Procedures:

1.      Say AAAAA steadily to the microphone while recording, and make sure the graph is in clear pattern.

2.      Let a different team member to say AAAAA again and record the pattern, compare with previous one.

3.      Collect data from a tuning fork by stinking it on a soft object. Compare with previous two.

4.      Measure the hair by using micrometer and compare with the calculated hair thickness.

Results:

       Values collected and calculated as shown:

	Collecting time / s	Patterns On the screen	Period / s	Frequ -ency / Hz	Wave -length / m	Amplitude		Theoretical Frequency of fork
First Person	0.03	3	0.01000	100	3.40	0.40		384 Hz
Second Person	0.03	8.5	0.00353	283	1.20	0.25		Speed of sound
Tuning Fork	0.03	11.5	0.00261	383	0.89	0.20		340 m/s

       The experimental frequency of the tuning fork is close to the theoretical one, thus the data is good. For different people saying AAAAA, the pattern dose not change while both the frequency and amplitude change. Also, by striking tuning fork lighter, the pattern and frequency of the sound wave produced does not change while the amplitude changed.
       Pattern for human voice of AAAA:

       
       Pattern for tuning fork:

       

Discussion:

       The experiment came with good data. By investigating the pattern, we found that certain sound of language may be carried in different loudness or frequency, but they will be in same pattern.